In-Line Ultrasonic Attenuation End Treatment For Use With An Ultrasonic Gas Flow Meter

ABSTRACT

An end treatment for use with an ultrasonic gas flow meter includes an attenuation section having a pipe extending in a longitudinal direction and containing alternating sets of laterally spaced and vertically oriented first and second solid wall plates located between an inlet end and an outlet end of the pipe. One plate includes a first end connected to an inside wall of the pipe and another plate includes a second end that extends past a longitudinal centerline of the pipe to define a gap between the end of the plate and a respective opposing inside wall of the pipe. As the gas traverses the plates by flowing through the gaps, the ultrasonic waves are prevented from reflecting back to the flow meter.

CROSS REFERENCE TO CO-PENDING APPLICATIONS

This application claims priority to U.S. patent application Ser. No.16/525,064, filed Jul. 29, 2019, which was a continuation-in-part ofU.S. patent application Ser. No. 15/589,701 filed May 8, 2017, U.S. Pat.No. 10,365,138, which claimed priority to U.S. Provisional ApplicationNos. 62/333,027 and 62/333,031, both filed May 6, 2016. All of which areincorporated herein by reference.

BACKGROUND

This disclosure relates to gas flow measurement equipment and, inparticular, to equipment, systems, and methods designed to improve theaccuracy of gas flow measurement in custody transfer transactions alonga gas pipeline. Because of the tremendous volume of gas beingtransferred between pipeline companies, small measurement errors canhave very large financial effects.

To measure gas flow through a pipeline, ultrasonic gas flow meters areplaced along a section of pipe. A front end treatment or elbow divertsthe main pipeline flow toward the flow meter and reduces swirl using aflow conditioner placed 10 pipeline diameters ahead of the flow meter.The conditioner provides a bullet-nosed gas flow profile into the meter.A backend treatment or elbow located at least 5 pipeline diameters afterthe meter brings the now-measured gas flow back in line with the mainpipeline (see FIG. 1). The backend elbow, along with a blind flangelocated opposite the main pipeline, helps attenuate ultrasonic wavesgenerated by downstream equipment such as a control valve and preventsthose waves from traveling back to the flow meter and interfering withflow measurement.

The use of elbows at the front and back end of the flow meter sectionwidens the footprint of the section. Therefore, a wide skid must bebuilt to support the section and special permits must be obtained totransport the skid to the job site. A need exists for an ultrasonicattenuation treatment that can eliminate the use of elbows.

SUMMARY

Embodiments of an end treatment for use with an ultrasonic gas flowmeter include an attenuation section having a pipe extending in alongitudinal direction and containing a set of alternating, spaced, andvertically oriented first and second plates located between an inlet endand an outlet end of the pipe. Each plate includes a first end connectedto an inside wall of the pipe and a second end extending past alongitudinal centerline of the pipe to define a gap between the end ofthe plate and a respective opposing inside wall of the pipe. As the gastraverses the plates by flowing through the gaps, the ultrasonic wavesreflect off the plates, toward other plates or the pipe wall and notback to the ultrasonic gas flow meter.

In some embodiments, the first plates extend from a top inside wall ofthe pipe and the second plates extend from the bottom inside wall of thepipe. The second plates, when arranged as bottom plates, may include amouse hole located toward the first end to prevent pooling ofcondensate.

The inlet and outlet ends may have a first inside diameter D1 and asecond inside diameter D2, D2>D1, with the pipe being at the secondinside diameter D2. The gap can be sized to be less than the firstinside diameter D1. In some embodiments, the gap is sized to half thatof the first inside diameter D1. The second inside diameter D2 may be atleast twice that of the first inside diameter D1. The inlet end can bearranged for D1 to D2 flow and the outlet end can be arranged for D2 toD1 flow. The inlet and outlet ends may include an eccentric reducer.

A method of attenuating ultrasonic waves originating from downstream ofthe ultrasonic gas flow meter is also disclosed. Embodiments of themethod include causing a gas flow that exits the ultrasonic gas flowmeter to traverse an attenuation section that includes a pipe extendingin a longitudinal direction and containing a set of alternating, spaced,and vertically oriented first and second plates located between an inletend and an outlet end of the pipe, wherein each plate includes a firstend connected to an inside wall of the pipe and a second end extendingpast a longitudinal centerline of the pipe to define a gap between theend of the plate and a respective opposing inside wall of the pipe.

An end treatment of this disclosure, and method of its use with anultrasonic gas flow meter, may include an attenuation section having apipe extending in a longitudinal direction, the pipe containing at leasttwo alternating sets of laterally spaced, vertically oriented, solidwall first and second plates located between an inlet end and an outletend of the pipe; the first plate of each set including a first endconnected to an opposing inside wall of the pipe and a second end, thesecond end of the first plate not contacting a respective opposinginside wall of the pipe to define a gap; the second plate of each setincluding a first end and a second end, the second end extending past alongitudinal centerline of the pipe and not contacting the respectiveopposing inside wall of the pipe to define another gap. In embodiments,the first end of the second plate may be connected to another opposinginside wall of the pipe. In other embodiments, the first end of thesecond plate is not connected to the opposing inside wall of the pipe todefine yet another gap. The first end of the first plate may not extendpast a longitudinal centerline of the pipe. The first and second platesmay be oriented at an oblique angle relative to the longitudinalcenterline of the pipe. In other embodiments, the first and secondplates are oriented perpendicular relative to the longitudinalcenterline of the pipe. The inlet and outlet ends may include aneccentric reducer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a prior art gas flow meter or measurement section of a gaspipeline.

FIG. 2 is top plan view of an embodiment of an inline ultrasonicattenuation end treatment.

FIG. 3 is an end view of the end treatment.

FIG. 4 is a side elevation view of the end treatment.

FIG. 5A is an embodiment of a reflective plate having a 45° bevel on theradial edge of the plate.

FIG. 5B is a front elevation view of a notch or mouse hole locatedtoward a pipe wall end of a reflective plate.

FIG. 6 is front elevation view of an embodiment of an effects isolatorthat may be used as part of an inline front end treatment in combinationwith the inline ultrasonic attenuation end treatment.

FIG. 7 is top plan view of the effects isolator.

FIG. 8 is top plan cross section view of an effects isolator of thisdisclosure.

FIG. 9 is a view taken along section line 9-9 of FIG. 8.

ELEMENTS AND NUMBERING USED IN THE DRAWINGS AND DETAILED DESCRIPTION

-   5 Inline ultrasonic attenuation end treatment-   10 Pipe section-   11 Inlet end having a first inside diameter D1-   13 Reducer located toward 11 (e.g. 12″ to 16″)-   15 Attenuation section (e.g. 16″)-   16 Longitudinal centerline-   19 Reducer located toward 21 (e.g. 16″ to 12″)-   21 Outlet end-   23 Second (inward) end of 25-   25 Plate-   27 First (pipe wall) end of 25-   29 Mouse hole-   31 Gap-   35 Effects isolator-   40 Flow conditioner-   41 Perforated plate-   43 Central aperture-   45 Aperture array-   50 Tube bundle-   53 Central vane-   55 Vane bundle or array-   57 Portion of plate 25 crossing centerline 16-   D1 First inside diameter-   D2 Second inside diameter

DETAILED DESCRIPTION

In embodiments of an inline ultrasonic attenuation end treatment 5,ultrasonic waves are prevented from interfering with an ultrasonic gasflow meter by a series of alternating plates.

Referring first to FIGS. 2 to 5B and 8 to 9, the end treatment 5includes a pipe section 10 with two different size inside diameters D1,D2 located between and inlet end 11 and outlet end 21, with D2>D1. Theends 11, 21, which may be arranged for connection to a respectiveopposing end of a main pipeline, have the first inside diameter D1.Located between the two ends 11, 21 are eccentric reducers 13, 19 and anattenuation section 15. (Concentric reducers may be used but eccentricreducers can prevent puddling.) Eccentric reducers 13, 19 also have thesecond inside diameter D2. Reducer 13 is arranged for D1 to D2 flow.Reducer 19 is arranged for D2 to D1 flow.

Attenuation section 15 also has second inside diameter D2 extendingalong its entire length and includes a set of alternating, horizontallyspaced, and vertically oriented plates 25A, 25B. In embodiments, plates25A are top plates and plates 25B are bottom plates. The second (inward)end 23 of the plate 25 can be beveled and the first (pipe wall) end 27may include a mouse hole 29 for drainage.

The attenuation section 15 may be sized so that an effective insidediameter provided by a set of two alternating plates 25A, 25B is thesame as that of the first inside diameter D1. Each plate 25 can extendpast the section's longitudinal centerline 16 to eliminate any straightline path back to the flow meter. Therefore, to reach the ultrasonic gasflow meter and interfere with its measurement, any ultrasonic wave beingreflected back toward the flow meter must traverse the set ofalternating reflective plates 25. However, each plate 25 causes the waveto reflect back to an adjacent plate 25 or the pipe wall

In embodiments, plates 25A, 25B may be laterally spaced apart as a setof plates so that at least a portion 57 of one plate 25A or B intersectsthe longitudinal centerline 16 of the section 15 whereas the portion 57of the other plate 25B or A of the pair does not. Another set of plates25 A, 25B may be arranged in an alternating fashion to that of thefirst. The plates 25 may be vertically oriented, solid wall plates. Thefirst plate 25A of each set may include a first end 27 connected to anopposing inside wall of the pipe and a second end 23 not contacting arespective opposing inside wall of the pipe to define a gap 31. Thefirst end 27 of the first plate 25A may not extend past a longitudinalcenterline 16 of the pipe. The second plate 25B of each set may includea first end 27 not contacting another opposing inside wall of the pipeto define another gap 31 and a second end 23 extending past alongitudinal centerline 16 of the pipe but not contacting the respectiveopposing inside wall of the pipe (to define yet another gap 31). Thegaps 31 provide flow channels for the gas and the plates 25 preventultrasonic waves from propagating back to the flow meter. In someembodiments, the first end 27 of the second plate 25B may be connectedto another opposing inside wall of the pipe. The first and second plates25A, 25B may be oriented at an oblique angle relative to thelongitudinal centerline 16 of the pipe. In other embodiments, the firstand second plates 25A, 25B are oriented perpendicular relative to thelongitudinal centerline 16 of the pipe. The inlet and outlet ends 11, 21may include an eccentric reducer 13, 19.

The inline ultrasonic attenuation end treatment 5 can be used incombination with a front end treatment including an effects isolator.The effects isolator can eliminate the need for end treatment upstreamof the ultrasonic flow meter and can be used in combination with thein-line ultrasonic attenuation treatment end.

Referring now to FIGS. 6 and 7, embodiments of an effects isolator 35may include a flow conditioner 40 or a flow conditioner 40 connected toor spaced from a tube bundle 50. The flow conditioner 40 may be the sameor similar to that disclosed in U.S. Pat. No. 5,341,848 and include aperforated plate 41 having a central aperture 43 with one or moreapertures 45 arrayed about it. The flow conditioner 40 can help developthe desired bullet-nosed flow profile for flow into the ultrasonic gasflow meter. Similar to the attenuation end treatment, the front endtreatment may be an in-line treatment end.

The tube bundle 50 may include a longitudinally extending central vane53 corresponding to the central aperture 43 of the flow conditioner 40and a bundle or array of longitudinally extending vanes 55 arrangedabout the central vane 53. The size and number of vanes 45 correspond toa respective size and number of apertures 45 in the flow conditioner 10.Preferably, the vanes 53, 55 are about the same diameter as the flowconditioner's 40 perforations.

Although embodiments of an inline ultrasonic attenuation end treatmenthave been described with reference to particular means, materials andembodiments, the end treatment is not intended to be limited to thoseparticulars. Rather, the description extends to all functionallyequivalent structures, methods, and uses, such as are within the scopeof the following claims.

What is claimed:
 1. An end treatment for use with an ultrasonic gas flowmeter, the end treatment comprising: an attenuation section including apipe extending in a longitudinal direction, the pipe containing at leasttwo alternating sets of laterally spaced, vertically oriented, solidwall first and second plates located between an inlet end and an outletend of the pipe; the first plate of each set including a first endconnected to an opposing inside wall of the pipe and a second end, thesecond end of the first plate not contacting a respective opposinginside wall of the pipe to define a gap; the second plate of each setincluding a first end and a second end, the second end extending past alongitudinal centerline of the pipe and not contacting the respectiveopposing inside wall of the pipe to define another gap.
 2. The endtreatment of claim 1 further comprising the first end of the secondplate connected to another opposing inside wall of the pipe.
 3. The endtreatment of claim 1, further comprising the first end of the secondplate not connected to the opposing inside wall of the pipe to defineyet another gap.
 4. The end treatment of claim 1 further comprising thefirst end of the first plate not extending past a longitudinalcenterline of the pipe.
 5. The end treatment of claim 1 furthercomprising the first and second plates oriented at an oblique anglerelative to the longitudinal centerline of the pipe.
 6. The endtreatment of claim 1 further comprising the first and second platesoriented perpendicular relative to the longitudinal centerline of thepipe.
 7. The end treatment of claim 1 further comprising the inlet andoutlet ends including a first inside diameter D1 and the pipe includinga second inside diameter D2, D2>D1.
 8. The end treatment of claim 1,further comprising a flow conditioner located upstream of the inlet end.9. The end treatment of claim 1 further comprising the inlet and outletends including an eccentric reducer.
 10. The end treatment of claim 1wherein at least one of the first and second plates is semi-circularshaped.
 11. A method of attenuating ultrasonic waves originating from adownstream source, the method comprising: causing a gas flow exiting anultrasonic gas flow meter to traverse an ultrasonic wave attenuationsection including: a pipe extending in a longitudinal direction, thepipe containing at least two alternating sets of laterally spaced,vertically oriented, solid wall first and second plates located betweenan inlet end and an outlet end of the pipe; the first plate of each setincluding a first end connected to an opposing inside wall of the pipeand a second end, the second end of the first plate not contacting arespective opposing inside wall of the pipe to define a gap; the secondplate of each set including a first end and a second end, the second endextending past a longitudinal centerline of the pipe and not contactingthe respective opposing inside wall of the pipe to define another gap.12. The method of claim 11 wherein the first end of the second plateconnected to another opposing inside wall of the pipe.
 13. The method ofclaim 11, wherein the first end of the second plate is not connected tothe opposing inside wall of the pipe to define yet another gap.
 14. Themethod of claim 11 wherein the first end of the first plate does notextend past a longitudinal centerline of the pipe.
 15. The method ofclaim 11 wherein the first and second plates are oriented at an obliqueangle relative to the longitudinal centerline of the pipe.
 16. The endtreatment of claim 1 wherein the first and second plates are orientedperpendicular relative to the longitudinal centerline of the pipe. 17.The method of claim 11 wherein the inlet and outlet ends include a firstinside diameter D1 and the pipe includes a second inside diameter D2,D2>D1.
 18. The method of claim 11, further comprising passing the gasflow through a flow condition prior to the ultrasonic gas flow meter.19. The method of claim 11, wherein at least one of the inlet and outletends include an eccentric reducer.
 20. The method of claim 11 wherein atleast one of the first and second plates is semi-circular shaped.